Living Sanibel: Glossy Ibis

July 23, 2012

Like the cattle egret's natural migration, the glossy ibis probably made its way to this side of the Atlantic from Western Africa via the trade winds or possibly caught up in hurricane winds. It was first seen along the northern edge of South America and has been expanding its range ever since. The glossy ibis is the most widespread ibis species in the world, with populations in Europe, Asia, Africa, Australia, South America, and North America. Similar in behavior to the cattle egret, the glossy ibis is rapidly acclimatizing to urban and suburban developments. This adaptable bird can often be found foraging along the grassy fringes of parking lots, ball fields, and agricultural areas. The North American population is still expanding, moving into coastal Georgia, South Carolina, and all the way north into Maine.

The brownish immature glossy ibis can easily be mistaken for an immature white ibis. Both birds achieve adult plumage within the first year, however, after which it is all but impossible to confuse the two. The glossy ibis is slightly smaller than the white ibis. Both birds wield distinctive de-curved bills, which they use to ferret out insects, crayfish, grasshoppers, snakes, and grubs. They use these long, slender bills to probe deeply into soft, damp soil in search of prey. Unlike the white ibis, the glossy ibis is rarely found along the coastal beaches, preferring the near-coastal and mainland regions of Florida.

The glossy ibis nests in colonies of other herons and egrets. Its nests are subject to predation by snakes, raccoons, bobcats, opossums, and rats. The adult bird is taken by alligators, great horned owls, and bald eagles, but its reproductive abilities are such that the statewide population is still increasing. Its exceptionally long life span, up to 21 years, is also a factor in its ability to flourish.